Composite porous metal article



4 w. e. CALKINS Q 8 COMPOSITE POROUS METAL ARTICLE Filed Nov. 10, 1939' I 1-VVENTO WILLIAM G. GAL/(1N6 A TTORNE VS;

i site article of V, in: the same: 7 7

1 having, the character J More particularly,

the provislonof an and p n. i 1A iilrtherobiectfof the invention is to provide to provide cbj'ects'the provision 'lnga ferrous metal tion,

facturepf the improved ring.

sectional view taken on .nnez-ao na 1 Fig. 3 isja side elevatlonal view,

new Dec. 28. 1943 COMPOSITE William G. Calkins, Detroit; Mich, 'a'ssiinor to I Chrysler Corporation, Highland rark, lldich., a

corporation of Delaware Application November 10, 1939, Serial No. 303,926

.5 Claims. (ensue-44') invention relates toan improved compomanufactureand method of mak- An obiect of m invennon is the provision of r animproved composite article of'manufacture a foraminous metal bearing surface of' substantial lubricant which-has a absorbing-capacity. i

an objectof the invention is improved packing ring havlng -ga relatively low coelhcient oi friction and whichhasflimproved characteristics or strength elasticity.

a composite packing ring especially adaptedffor uscg n coniunction with a piston foran internal combustion engine and which has .a'bearlng surhaving asubstahtial lubricant absorbing capacity a 20 iormedbya layer of porous metal hearing by whicnthe structure is improved from the standpoint'oi scumng and wear.

Fig. 7 isaside elevational view of a modified I form of the ring.

Sis a sectional view taken on the line 8-8 ofFig.7.

.Fig. 9 is a side-elevational' view of a piston, 'partly in'section, embodying the rings shown in Flee. 6 and 7.

. The apparatus shown in Figs. 1 to 3 is especlally adapted for manufacture of the form of rings illustrated in Figs. 4, 5 and 6'. This apparatus includes a suitable main die block l0, pref-v .erably ofhardened-steel and provided with a longitudinal slotted recess il in which the blade I 2 of a 'clrcularbriquetting roll l3 fits with rela-' tively close clearance. Suitable means (not shown) may "be provided for drivingthe roll l3 Another object of the invention is the provision -01 anim'proved method for manufacturing articles otthe foregoing type, and more especially i improved method'forsecuring a ioraminous bearing .forming'material' to a rein forcing backing. or sup'port so that'the bearing i y bonded to the supma al'fisj "preferably the inventionias for its I of an improved method for manufacturing a composite ring-like member, such as a piston packing ring, preferably includ- More. particularly,

anda sheet-like porous bearing metal layer rigid,- ly bonded thereto to provide a bearing surface;

I to-providean improvedmethod for securinga mixtureoi finely divided particles of different materials ltosa support or backing of. the fore i going type sothat the resulting assembly, including the backing or'support and the bea'ring' form- .lng-layemcan be deformedto the'desired shape fi d (contour without impairing the structural characteristics thereof. ,1 I Other objects and advantages of the invention will be more apparentirom the following de- 'scrlption taken in connectionwith the accomdmwing, wherein: Fig. )1 isa side elevational view, partly-in secillustrating a suitable apparatus for manu- Flg. 2 is 'a 've'rtical Part y in section,-of a modified form of a portionof the apparatus shcwnin Fig.1. h J

Fig. its a view in perspective of a blank prior to deformation thereof into ring shape.

Fig. 5 isa side elevational view of the ring. Big. 6 is a sectional view taken on line 6-6 oi.

support orreinforcing part and the latter is supported bybearings indicated at It which are vertically adjustable through the -pinsl5 and the calibrated springs 16 in order to provide for pressure and size adjustment.

An elongated stock for the backing or support part ll of the'rlng; shown in Figs. 4, 5, 6 is preferably, formedto the desired-shape in cross- .j --section,f the recess. of the block I01 being shaped toja'ccommodate the stock and is suitably fedthrough this recess. In addition to the part ll, the ring has an outer portion i8 adapted to contact or engage the wall of the bore, forexampie, within which the piston andring assembly operates. .The portion l8 preferably comprises a mixture'of powdered metals in a finely divided state and such other-ingredients as may be deroll l2 and'the dieblock sired.as' will more fully hereinafter appear. The

mixture is deposited in a hopper l9 from whichv it is fed by ac'onduit 20 to the upper side of the part I1 and passed with the latter between the l0 and'compressed to the desired thickness. The mechanism indicated at '2! is adjustable to predetermine and control the amount of themixture fed from the hopper. While alarge variety of. mixtures of powdered metals and other ingredients may be used, it has been found that the following composition provides a satisfactory structure where same is embodied ina piston packing ring, as illustrated herein: I

a Percent by a weight Powdered copper; 88.5

Powdered n a 10.00

Powdered graphite 1.50

The, percentages'of the materials used in the foregoing composition may bevaried, the particular proportions recited being given merely as an example of a composition which, it has been found, may. be readily compressed according to the methodherein disclosed. Any suitable solid lubricating 7 material such powdered boric 'acid may be used in place of graphite and in some i 7.

a's exfoliate mica; or

such asord'inary lubricating oil maybe employed.

Disposed adjacent the discharge end of the 4 block I is a furnace 22 having an inlet opening 23 registering with the latter for receiving the composite stock as it is discharged from the block and roller, and an outlet opening". Theor reinforcing ferrous metalelement ll' encased metal 18* of a is shown in Figs.

. ring i'l', providing a furnace preferably has a non-oxidizing reducing either hydrogen or illuminating gas of a reducing atmosphere to the interior thereof for sintering and bonding. The furnace is preferably maintained at a temperature slightly above the melting point'ofone of the powdered metal constituents of the mixture and below the melting point of the other metal. Thus, themetal havin the lower melting point fuses with surface portions of the metal having the higher melting point so as to be firmly bonded to-' gether while leaving sufficient voids therein to render the resulting product .foraminous or porous throughout, and capable of retaining a substantial-lubricant absorbed content, At the same time the part I8 is rigidly bonded. to the part H, the latter preferably being a ferrous met- 9.1 such as steel for example where the structure is embodied in a. packing ring. For the purpose of creating. pressure on the stock to provide a better bond, a roller 25-, positioned within the furnace, engages the stockas it is passed through the-latter.

I The assembly as received from the furnace may be of such length as'desired, it being understood that it preferably has a flat contour, and theassembl'y may be cut to the desired lengthor if desired the assembly may initially have the re- .quired length-for the article,--all as shown in l ig. 4. Sufiicient'excess stock of both parts l1 and I8 is allowed for finish grinding, turning or other machining operation which .may be de-. sired; For the manufacture of. piston packing atmosphere provided, for example, by. supplying a ring, for example.

charge of the mixture to ders'tood that various changes departing fromthe spirit of by a mass'of sintered powdered composition as set forth for the ring 28. In this form-of the invention the metal 18' encases the idly bonded thereto.

The ring 26' can placing a charge of the mixture of finely divided particles in a female die part suitablypositioning the core l'l' therein, feeding'an additional, cover thejcore ll and compressing with a suitable male diepart to briquette the powdered metal mixture. The resulting assembly may then be passed through a furnace as illustrated at 22 to sinter the mixture and bond the same to the core I'I.',-as set forth in connection with the ring 28, and the required machining and forming, operations performed as specified heretofore to provide split ring 28'".

In Fig. 9 there is ventionally used in internal combustion engines, utilizing the packing rings 26 and 28'. The p9- rous metal'parts l8 rings provide a porous bronze bearing surface which has a relatively low coeflicient of friction and which, by reason f capillary lubricant on; tribution, is particularly advantageous from the and wear.Furth f orc,'

standpoint of scumng I the steel support or reinforcing parts-I1 and I1 lends to the ring strength and Although but two embodiments mm mmtion is herein shown and described, it will and arrangement of parts may our said invention other is not our intention to limit than by the terms of the appended formed after the assembly has assumed the shape 7 illustrated in P18. 5."

After the assembly has passed through the as. i

nacea may be submerged in a suitable oil bath so as to impregnate the porous metal layer with 9. suitable lubricant. However, where the 8151110:

ture is embodied in a piston packing ring this' operation is not necessary inasmuch as the ring so will be subjected to an oil bath during conventional operation inthe cylinder bore.-

Referring to Fig. 3 wherein there is illustrated a modified form of a portion of the apparatus A suitable supporting member 21 is provided for -the worklas it is subjected to pressure between vthe rolls 1! and It. The modified form is par; ticularly adapted for use where relatively highunit pressure are required, and pressure adiustin: mechanismsimilar to that embodied in the of annular resilient split tin riiiidl'y surface bonded What 1 claim:

L-A piston packing tic reinforcing backing and a bearing portion engageable with the wall, of-the bore receivint the piston and comprising a sheet-like porous bearing metal layer rigidly bonded thereto.

2. A piston packing ringincludlng a ferrous metal insert supporting part and a bearing portion engageable with the metal rigidly bonded thereto.

3. Apiston packing V split reinforcing steel ring and a relatively thin layer of bearing'msterial secured to said and engageable with the-wall of the bore receiv ing. the piston, said material comprising of foraminous sintered powdered metal havlnl a plurality of voids therein adapted'to absorb n substantial lubricantcontent. s 5 v 4. Ida piston packing ring; the combination steel backing and a porous. bearing portion consisting of mixture of finely divided particles of-coppor to the outer face of said backing. 1 1

5.111 a piston ung ring, the seams ofan annular ferrous metal core, and a beorlnl forming surface enveloping said core and comprising a mass of sintered porous bearing matcrial surface bonded to said core. 1

bearing surface for each of the four sides of the ring, andis directly and rigbe produced, for example, by

the

illustrated a piston 28, con-.

and I8 of these respective elasticity is: in excess of the properties obtainable in a cast iron be tin. in the size.- shall! be made without: invention and it including a split sin-1:

wallof the may, 8 the Piston and comprising porous 'mainshowingmaybe'utilized.- Q- 

